CORS error in Firefox incognito mode only
Hi there, I am working on a site with Segment API and need to load their JS on my site for it to work. Whats happening is, I get the following error: "Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://api.segment.io/v1/p. (Reason: CORS request did not succeed). Status code: (null)."
The weird part is, it happens only in Firefox incognito mode. It works on Chrome, Edge, Opera.
I am wondering if this is by design or if it is a bug.
Firefox version 98.0 (64-bit).
פתרון נבחר
Is it a background request (fetch or XMLHttpRequest), or a regular script tag?
CORS background requests definitely require an Origin header. I wonder whether that is suppressed in private windows with some requests? You could inspect the headers in the Network panel of the Dev Tools. More info on that panel: https://developer.mozilla.org/docs/Tools/Network_Monitor
If it's a regular script tag, this could be due to Tracking Protection (by default, stricter in private windows) or an add-on that blocks analytics scripts. For Tracking Protection, click the shield icon at the left end of the address bar to check what is being blocked. With add-on blockers, the UI varies, but the toolbar button usually gives you an info panel.
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פתרון נבחר
Is it a background request (fetch or XMLHttpRequest), or a regular script tag?
CORS background requests definitely require an Origin header. I wonder whether that is suppressed in private windows with some requests? You could inspect the headers in the Network panel of the Dev Tools. More info on that panel: https://developer.mozilla.org/docs/Tools/Network_Monitor
If it's a regular script tag, this could be due to Tracking Protection (by default, stricter in private windows) or an add-on that blocks analytics scripts. For Tracking Protection, click the shield icon at the left end of the address bar to check what is being blocked. With add-on blockers, the UI varies, but the toolbar button usually gives you an info panel.
Hi @jscher2000, thanks for the response.
Disabling the Enhanced Tracking Protection worked.